With earnings season in full swing, traders had no lack of corporate news to parse through. Three Dow components, plus bellwether United Parcel Service (UPS), posted results ahead of the opening bell.

DuPont (DD) posted third-quarter earnings of 44 cents a share, two cents shy of expectations. The blue-chip chemical maker's sales of $7.4 billion also trailed the Street's view of $8.15 billion. DuPont also said it expects to earn between $3.25 and $3.30 for the full year, far behind forecasts of $3.93.

3M (MMM) unveiled a third-quarter profit of $1.65 a share, matching expectations. The company’s sales of $7.5 billion came in short of the Street’s forecast of $7.6 billion. The Dow component also cut its full-year outlook to a range of $6.27 to $6.35 a share from $6.35 to $6.50 a share, partially due to an acquisition-related charge.

United Technologies (UTX) revealed adjusted quarterly earnings of $1.37 a share, better than the $1.18 a share Wall Street expected. The diversified manufacturer's revenues of $15.04 billion came in sort of estimates of $15.51 billion. The company re-affirmed its full-year profit guidance, but narrowed its sales guidance to $58 billion from a range of $58 billion to $59 billion.

United Parcel Service’s (UPS) adjusted third-quarter profit of $1.06 a share came in line with estimates. However, the package delivery company’s sales came in at $13.07 billion, missing forecasts of $13.31 billion. The company, which is seen as an economic bellwether, also updated its full-year guidance to a range of $4.55 to $4.65 a share, compared to estimates of $4.56 a share.

Also on the corporate front, technology behemoth Apple (AAPL) was expected to reveal its much-anticipated mini version of its iPad tablet on the day. Target (TGT) revealed plans to sell its credit card portfolio to TD Bank.

The economic calendar remained light on Tuesday. A regional manufacturing report from the Richmond Federal Reserve was due at 10:00 a.m. ET. The Federal Reserve's two-day monetary policy meeting was also set to kick off on the day.

Worries also continued swirling about Spain, the eurozone's fourth-biggest economy. The country's economy shrunk 0.4% in the third quarter, the fifth-straight quarterly contraction. Moody's also cut its rating on five regions across the country, another potentially destabilizing blow for the country that is struggling to control its borrowing costs.

Commodities followed equities sharpy into the red. The benchmark crude oil contract traded in New York tumbled $1.36, or 1.5%, to $87.30 a barrel. Wholesale New York Harbor gasoline slid 1.6% to $2.605 a gallon.

In metals, gold dropped $17, or 0.98%, to $1,710 a troy ounce.

Foreign Markets

The Euro Stoxx 50 sold off by 1.3% to 2497, the English FTSE 100 dropped 1.1% to 5817 and the German DAX tumbled 1.4% to 7223.

In Asia, the Japanese Nikkei 225 rose 0.04% to 9014 and the Chinese Hang Seng climbed 0.68% to 21698.